1. Field of the Invention
The invention relates to antenna elements, generally, and particularly to an antenna element which can be used to form a scanning array over bandwidths approaching two octaves.
2. Related Art
Crossed dipole (or turnstile antennas), grid dipoles and wire biconical antennas have been used alone and in arrays in a variety of communications and radar applications. C. Balanis in Antenna Theory Analysis and Design (1982) discloses at page 330 that biconical antennas have broadband characteristics useful in the VHF and UHF frequency ranges, but that the size of the solid shell biconical structure limits many practical applications. As a compromise, multi-element intersecting wire bow antennas have been employed to approximate biconical antennas. Johnson and Jasik in the Antenna Engineering Handbook (1984) disclose crossed dipole antennas at page 28-10.Such antennas are used for producing circular polarization. Johnson and Jasik at page 4-12 also disclose biconical dipoles.
To date, however, there has been no disclosure of an antenna element that provides the desirable feature of a bandwidth approaching two octaves in an array environment by stacking two crossed dipoles with the relative dimensions described below.